Apocolipse

Yessir. I’m curious the outcome once he reduces compression with those pistons if the 2k rpm issue is still there. I have a feeling mine is too high but would love to cross it off as yup that’s what it is vs guessing. It appeared after swapping to a smaller cam so higher dca

Sub8

​​​​​​​But that's also kinda my point, when I said just live with it. It's not damaging anything, although there is a fatigue issue in the background. We do tend to get hung up on stuff that' isn't really anything to be worried about.

pierrel

Cant really say if it was using abnormal amounts of oil, drove about 2500 miles last year and i filled to the middle mark at spring and had slightly lower when i drained the oil. Car was tuned in Open loop at idle - 1500 rpms at lambda 1.02. Dont really know if that would leave marks in combustion chambers and pistons?

Im the owner since the last 6 years I think. I was the one who had the current Mahle pistons put in. Little did i know about the added compression height following Mahles guide which said 70cc chambers would yeild 11.5 : 1 CR.
Engines been a part pretty much every winter. Ive been fighting valve guide wear after putting in a copper based sleeve (K-line) in the valve guides together with the stock intake valves. Last year i finally got fed up with it and went with AHPs TI valves and Moldstar90. Going to have my head guy check them out in a week or two, hoping to find everything to be in order.

Car was bought as a HCI car with a BTR 4 camshaft in it and stock pistons. Was lead to believe the stock pistons were crap and had them replaced first winter.

Alright, thanks for clearing that up. Easy to misinterpret these things...
Yeah. Sad thing is it could be a multitude of things, like the intake seals/ports being messed up, or compression, or both... Now, since I'm changing multiple things at once, i wont be able to say 100% what caused it.

You are absolutely correct sir. But, whenever I've heard the sound, I've almost immediately backed out of it. There's only been a few times where the logger has showed KR, but no audible note, that I've keep the foot in to get it on the log.

Being that I hear it audibly sometimes, I don't feel comfortable leaving it as is. And since I do a long road trips around Europe during summer, in warm weather and sometimes high altitude, AND track/road course driving in 20 min sessions, its going to be more fun in the long run to have a potentially slightly less HP making engine, but a engine that just keeps on running. Fingers crossed...
But I totally agree, sadly I'm often finding myself looking way to much into an issue, that really isn't an issue.

OneMeanZ

Really curious to hear the results of this...I have the exact set up as well.

Apocolipse

I hear you there - just annoying pulling 8-10deg from the timing map in the 2k region to stop it from happening - im sure I’m losing torque.

Pb82 Ronin

Another situation in which the J&S Interceptor would work wonders.

Sub8

Yes it is😬. But in terms of impact to the actual driving experience or durability of the motor. Would you know if you didn't log it?

Apocolipse

Could create a condition of early cat failure with higher egt since timing is pulled so much - otherwise nope